A PE teacher caught sending pornographic Christmas cards to pupils after a parent recognised his handwriting from a school report is facing a possible jail term.

Mark Walsh, 29, from Derwent Road, Farnworth, near Bolton, created the explicit "home-made" cards with porn pictures from the internet.

He also stole teenage girls' clothing from the changing rooms while they had PE lessons.

Walsh pleaded guilty at Bolton Crown Court to three charges of abusing his position of trust by causing or inciting children to engage in sexual activity by sending the cards over Christmas in 2004. The charges relate to three 14-year-old girls.

Neither they nor the school involved can be named, for legal reasons.

Walsh, who also teaches geography and maths, pleaded not guilty to four other similar charges over the cards and asked for 10 offences of theft relating to the clothing to be taken into consideration.

Walsh made his pornographic Christmas cards by downloading images from the internet.

But he was caught when one parent recognised his handwriting from a school report for her daughter. Police later found the pictures on his computer and also a "fantasy league" of schoolgirl pupils, ranked as if on a football league table.

Nicola Gatto, QC, prosecuting, explained to the court: "This was not just an aberration that occurred on December 24."

Judge William Morris bailed Walsh until September 29 for sentence, on condition he does not approach any of the girls involved.

He added: "Clearly these are serious offences.

"You will understand, I am sure, I will have to consider the question of a custodial sentence."